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371. Survey of Class II sources in Taurus with ALMA
ID:
ivo://CDS.VizieR/J/ApJ/872/158
Title:
Survey of Class II sources in Taurus with ALMA
Short Name:
J/ApJ/872/158
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have conducted a survey of young single and multiple systems in the Taurus-Auriga star-forming region with the Atacama Large Millimeter Array (ALMA), substantially improving both the spatial resolution and sensitivity with which individual protoplanetary disks in these systems have been observed. These ALMA observations can resolve binary separations as small as 25-30au and have an average 3{sigma} detection level of 0.35mJy, equivalent to a disk mass of 4x10^-5^M_{sun}_ for an M3 star. Our sample was constructed from stars that have an infrared excess and/or signs of accretion and have been classified as Class II. For the binary and higher-order multiple systems observed, we detect {lambda}=1.3mm continuum emission from one or more stars in all of our target systems. Combined with previous surveys of Taurus, our 21 new detections increase the fraction of millimeter-detected disks to over 75% in all categories of stars (singles, primaries, and companions) earlier than spectral type M6 in the Class II sample. Given the wealth of other information available for these stars, this has allowed us to study the impact of multiplicity with a much larger sample. While millimeter flux and disk mass are related to stellar mass as seen in previous studies, we find that both primary and secondary stars in binary systems with separations of 30-4200au have lower values of millimeter flux as a function of stellar mass than single stars. We also find that for these systems, the circumstellar disk around the primary star does not dominate the total disk mass in the system and contains on average 62% of the total mass.
372. T dwarf companions around M, L, T dwarfs in IR
ID:
ivo://CDS.VizieR/J/ApJ/743/141
Title:
T dwarf companions around M, L, T dwarfs in IR
Short Name:
J/ApJ/743/141
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report observational techniques, results, and Monte Carlo population analyses from a Spitzer Infrared Array Camera imaging survey for substellar companions to 117 nearby M, L, and T dwarf systems (median distance of 10pc, mass range of 0.6 to ~0.05M_{sun}_). The two-epoch survey achieves typical detection sensitivities to substellar companions of [4.5um]<=17.2mag for angular separations between about 7" and 165". Based on common proper motion analysis, we find no evidence for new substellar companions. Using Monte Carlo orbital simulations (assuming random inclination, random eccentricity, and random longitude of pericenter), we conclude that the observational sensitivities translate to an ability to detect 600-1100K brown dwarf companions at semimajor axes >~35AU and to detect 500-600 K companions at semimajor axes >~60AU. The simulations also estimate a 600-1100K T dwarf companion fraction of <3.4% for 35-1200AU separations and <12.4% for the 500-600K companions for 60-1000AU separations.
373. TESS Input Catalog version 8.2 (TIC v8.2)
ID:
ivo://CDS.VizieR/IV/39
Title:
TESS Input Catalog version 8.2 (TIC v8.2)
Short Name:
IV/39
Date:
03 Mar 2022 07:19:26
Publisher:
CDS
Description:
We define various types of "phantom" stars that may appear in the TESS Input Catalog (TIC), and provide examples and lists of currently known cases. We present a methodology that can be used to check for phantoms around any object of interest in the TIC, and we present an approach for correcting the TIC-reported flux contamination factors accordingly. We checked all 2077 TESS Objects of Interest (TOIs) known as of July 21st 2020 (Sectors 1 to 24) and sent corrections for 291 stars to MAST where they are integrated into the publicly available TIC-8, updating it to TIC 8.1. We used the experience gained to construct an all-sky algorithm searching for "phantoms" which led to 34 million updates integrated into TIC 8.2.
374. TESS Input Catalog - v8.0 (TIC-8)
ID:
ivo://CDS.VizieR/IV/38
Title:
TESS Input Catalog - v8.0 (TIC-8)
Short Name:
IV/38
Date:
11 Feb 2022 14:26:27
Publisher:
CDS
Description:
The TIC is used to help identify two-minute cadence target selection for the Transiting Exoplanet Survey Satellite (TESS) mission, and to calculate physical and observational properties of planet candidates. It is for use by both the TESS science team and the public, and it is periodically updated - the current version is TIC-8. TIC-8 uses the GAIA DR2 catalog as a base and merges a large number of other photometric catalogs, including 2MASS, UCAC4, APASS, SDSS, WISE, etc. There are roughly 1.5 billion stellar and extended sources in TIC-8, containing compiled magnitudes including B, V, u, g, r, i, z, J, H, K, W1-W4, and G. This version was released in May 2019, and is expected to be the last official version of the TIC produced by the TESS mission, although future, independent development of the TIC is possible. The TIC is the responsibility of the SAO Arm of the TESS Science Office under the leadership of David Latham. The TESS Target Selection Working Group (TSWG) is co-chaired by Keivan Stassun (Vanderbilt) & Joshua Pepper (Lehigh).
375. TESS M-dwarf exoplanetary systems
ID:
ivo://CDS.VizieR/J/AJ/157/113
Title:
TESS M-dwarf exoplanetary systems
Short Name:
J/AJ/157/113
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a study of the M-dwarf exoplanetary systems forthcoming from NASA's TESS mission. While the mission's footprint is too complex to be characterized by a single detection completeness, we extract ensemble completeness functions that recover the planet detections from previous work for stars between 3200 and 4000 K. We employ these completeness functions, together with a dual- population planet occurrence model that includes compact multiple planetary systems, to infer anew the planet yield. We predict both the number of M-dwarf planets likely from TESS and their system architectures. We report four main findings. First, TESS will likely detect more planets orbiting M dwarfs that previously predicted. Around stars with effective temperatures between 3200 and 4000 K, we predict that TESS will find 1274+/-241 planets orbiting 1026+/-182 stars, a 1.2-fold increase over previous predictions. Second, TESS will find two or more transiting planets around 20% of these host stars, a number similar to the multiplicity yield of NASA's Kepler mission. Third, TESS light curves in which one or more planets are detected will often contain transits of additional planets below the detection threshold of TESS. Among a typical set of 200 TESS hosts to one or more detected planets, 93+/-17 transiting planets will be missed. Transit follow-up efforts with the photometric sensitivity to detect an Earth or larger around a mid-M dwarf, even with very modest period completeness, will readily result in additional planet discoveries. Fourth, the strong preference of TESS for systems of compact multiples indicates that TESS planets will be dynamically cooler on average than Kepler planets, with 90% of TESS planets residing in orbits with e<0.15. We include both (1) a predicted sample of planets detected by TESS orbiting stars between 3200 and 4000 K, including additional nontransiting planets, or transiting and undetected planets orbiting the same star and (2) sample completeness functions for use by the community.
376. TGAS distances
ID:
ivo://CDS.VizieR/J/MNRAS/478/3809
Title:
TGAS distances
Short Name:
J/MNRAS/478/3809
Date:
10 Dec 2021 00:51:19
Publisher:
CDS
Description:
We derive unbiased distance estimates for the Gaia-TGAS data set by correcting for the bias due to the distance dependence of the selection function, which we measure directly from the data. From these distances and proper motions, we estimate the vertical and azimuthal velocities, W and V_{phi}_, and angular momentum L_z_ for stars in the Galactic centre and anticentre directions. The resulting mean vertical motion W^-^ hows a linear increase with both V_{phi}_ and L_z_ at 10{sigma} significance. Such a trend is expected from and consistent with the known Galactic warp. This signal extends to stars with guiding centre radii R_g_<R_0_, placing the onset of the warp at R<=7kpc. At equally high significance, we detect a previously unknown wave-like pattern of W^-^ over guiding centre R_g_ with an amplitude ~1km/s and a wavelength ~2.5kpc. This pattern is present in both the centre and anticentre directions, consistent with a winding (corrugated) warp or bending wave, likely related to known features in the outer disc (TriAnd and Monoceros overdensities), and may be caused by the interaction with the Sgr dwarf galaxy ~1Gyr ago. The only significant deviation from this simple fit is a stream-like feature near R_g_~9kpc (|L_z_|~2150kpc.km/s).
377. TGU 619 stars spectral types and distances
ID:
ivo://CDS.VizieR/J/BaltA/20/317
Title:
TGU 619 stars spectral types and distances
Short Name:
J/BaltA/20/317
Date:
21 Oct 2021
Publisher:
CDS
Description:
Interstellar extinction is investigated in a 1.5 square degree area of the Cepheus Flare in the direction of the dark cloud TGU 619 at l=102.5{deg}, b=+15.5{deg} . The study is based on photometric classification of 658 stars in spectral and luminosity classes down to V=16mag using photometry in the Vilnius seven-color system published in Paper I (2009BaltA..18..161Z, Cat. J/BaltA/18/161). The extinction in the investigated area is very uneven: in the most transparent directions we find an extinction of 0.3-1.1mag while in the darkest directions the maximum extinction observed is 2.6mag. The real extinction should be considerably larger since in the direction of some cloud clumps no stars are seen. The distribution of stars in the AV vs. d plot gives evidence that the dust clouds are located at a distance of 286+/-20pc.
378. The AllWISE motion survey (AllWISE2)
ID:
ivo://CDS.VizieR/J/ApJS/224/36
Title:
The AllWISE motion survey (AllWISE2)
Short Name:
J/ApJS/224/36
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use the AllWISE Data Release to continue our search for Wide-field Infrared Survey Explorer (WISE)-detected motions. In this paper, we publish another 27846 motion objects, bringing the total number to 48000 when objects found during our original AllWISE motion survey are included. We use this list, along with the lists of confirmed WISE-based motion objects from the recent papers by Luhman (2014, J/ApJ/781/4) and by Schneider et al. (2016, J/ApJ/817/112), and candidate motion objects from the recent paper by Gagne et al. (2014, J/ApJ/783/121), to search for widely separated, common-proper-motion systems. We identify 1039 such candidate systems. All 48000 objects are further analyzed using color-color and color-mag plots to provide possible characterizations prior to spectroscopic follow-up. We present spectra of 172 of these, supplemented with new spectra of 23 comparison objects from the literature, and provide classifications and physical interpretations of interesting sources. Highlights include: (1) the identification of three G/K dwarfs that can be used as standard candles to study clumpiness and grain size in nearby molecular clouds because these objects are currently moving behind the clouds, (2) the confirmation/discovery of several M, L, and T dwarfs and one white dwarf whose spectrophotometric distance estimates place them 5-20pc from the Sun, (3) the suggestion that the Na I "D" line be used as a diagnostic tool for interpreting and classifying metal-poor late-M and L dwarfs, (4) the recognition of a triple system including a carbon dwarf and late-M subdwarf, for which model fits of the late-M subdwarf (giving [Fe/H]~-1.0) provide a measured metallicity for the carbon star, and (5) a possible 24pc distant K5 dwarf + peculiar red L5 system with an apparent physical separation of 0.1pc.
379. The Carnegie-Chicago Hubble Program. II. IC 1613
ID:
ivo://CDS.VizieR/J/ApJ/845/146
Title:
The Carnegie-Chicago Hubble Program. II. IC 1613
Short Name:
J/ApJ/845/146
Date:
21 Oct 2021
Publisher:
CDS
Description:
IC 1613 is an isolated dwarf galaxy within the Local Group. Low foreground and internal extinction, low metallicity, and low crowding make it an invaluable testbed for the calibration of the local distance ladder. We present new, high-fidelity distance estimates to IC 1613 via its Tip of the Red Giant Branch (TRGB) and its RR Lyrae (RRL) variables as part of the Carnegie-Chicago Hubble Program, which seeks an alternate local route to H_0_ using Population II stars. We have measured a TRGB magnitude I_ACS_^TRGB^=20.35+/-0.01_stat_+/-0.01_sys_mag using wide-field observations obtained from the IMACS camera on the Magellan-Baade telescope. We have further constructed optical and near-infrared RRL light curves using archival BI- and new H-band observations from the ACS/WFC and WFC3/IR instruments on board the Hubble Space Telescope (HST). In advance of future Gaia data releases, we set provisional values for the TRGB luminosity via the Large Magellanic Cloud and Galactic RRL zero-points via HST parallaxes. We find corresponding true distance moduli {mu}_0_^TRGB^=24.30+/-0.03_stat_+/-0.05_sys_mag and <{mu}_0_^RRL^>=24.28+/-0.04_stat+sys_mag. We compare our results to a body of recent publications on IC 1613 and find no statistically significant difference between the distances derived from Population I and II stars.
380. The distance modulus of the LMC
ID:
ivo://CDS.VizieR/J/A+A/363/L1
Title:
The distance modulus of the LMC
Short Name:
J/A+A/363/L1
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use double-mode RR Lyrae (RRd) stars from the MACHO variable star database of the Large Magellanic Cloud (LMC) to estimate its distance, by utilizing photometric data, linear pulsation and stellar atmosphere models. If we set E_(B-V)_=0.11 and [M/H]=-1.5 for LMC, we get M-m=18.52mag. The fact that the distance moduli obtained in this and in our former studies of cluster RRd and Small Magellanic Cloud beat Cepheids agree so well, implies that the only serious source of error is the zero point of the temperature scale, which should not have larger than +/-0.10mag effect on the distance modulus.

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